const fs = require('fs');
const path = require('path');
const zlib = require('zlib');
const rollup = require('rollup');
const terser = require('terser');

if (!fs.existsSync('dist')) {
  fs.mkdirSync('dist');
}

let builds = require('./config').getAllBuilds();

// filter builds via command line arg
if (process.argv[2]) {
  const filters = process.argv[2].split(',');
  builds = builds.filter((b) => {
    return filters.some((f) => b.output.file.indexOf(f) > -1 || b._name.indexOf(f) > -1);
  });
}
build(builds);

function build(builds) {
  let built = 0;
  const total = builds.length;
  const next = () => {
    buildEntry(builds[built])
      .then(() => {
        built++;
        if (built < total) {
          next();
        }
      })
      .catch(logError);
  };
  next();
}

function buildEntry(config) {
  const output = config.output;
  const { file, banner } = output;
  const isProd = /min\.js$/.test(file);
  return rollup
    .rollup(config)
    .then((bundle) => bundle.generate(output))
    .then(({ output: [{ code }] }) => {
      if (isProd) {
        terser
          .minify(code, {
            toplevel: true,
            output: {
              ascii_only: true, // 仅输出ascii字符
              comments: false,
            },
            compress: {
              drop_console: true,
              drop_debugger: true,
            },
          })
          .then((res) => {
            const minified = (banner ? banner + '\n' : '') + res.code;
            return write(file, minified, true);
          });
      } else {
        return write(file, code);
      }
    });
}

function write(dest, code, zip) {
  return new Promise((resolve, reject) => {
    function report(extra) {
      console.log(blue(path.relative(process.cwd(), dest)) + ' ' + getSize(code) + (extra || ''));
      resolve();
    }
    fs.writeFile(dest, code, (err) => {
      if (err) return reject(err);
      if (zip) {
        zlib.gzip(code, (err, zipped) => {
          if (err) return reject(err);
          report(' (gzipped: ' + getSize(zipped) + ')');
        });
      } else {
        report();
      }
    });
  });
}

function getSize(code) {
  return (code.length / 1024).toFixed(2) + 'kb';
}

function logError(e) {
  console.log(e);
}

function blue(str) {
  return '\x1b[1m\x1b[34m' + str + '\x1b[39m\x1b[22m';
}
